Contaminant-reactive geocomposite mat and method of manufacture and use

ABSTRACT

Reactive geocomposite mats, and their method of manufacture, for treating contaminants in sediment, soil or water that allow the passage of essentially non-contaminated water therethrough. The geocomposite mat includes a pre-formed woven or non-woven geotextile, that is needlepunched to an outer geotextile sheet layer to provide a high loft, structurally secured, pre-formed geotextile having a thickness of about 6 mm to about 200 mm, and having, a porosity sufficient to receive a powdered or granular contaminant-reactive material, contaminant-sorptive material, or a contaminant-neutralizing material (hereinafter collectively referred to as “contaminant-reactant material” or “contaminant-reactive material”) throughout its thickness, or in any portion of the thickness across its entire major surface(s). The powdered or granular contaminant-reactive material is disposed within the pores of the previously formed, high loft geotextile mat to surround the fibers, e.g., by vacuum or vibrating the high loft mat while in contact with the contaminant-reactive material to allow the powdered or granular contaminant-reactive material to flow by gravity into the pores of the previously formed, needlepunched geotextile. A liquid-permeable outer geotextile sheet then is secured to the filled geotextile, preferably by heating upwardly extending fibers of the pre-formed geotextile mat to prevent the powdered or granular material from escaping from the geotextile during transportation and installation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.11/599,080 filed Nov. 14, 2006 which is a continuation of applicationSer. No. 11/489,383, filed Jul. 19, 2006, which is a continuation ofapplication Ser. No. 10/718,128, filed Nov. 19, 2003.

FIELD OF THE INVENTION

The present invention is directed to a reactive geocomposite mat forcontrolling or preventing the further spread of contaminants in soil,sediment or water. More particularly, the geocomposite mat describedherein includes a reactive core formed from a high loft geotextile thatis filled or partially filled with a powdered or granular reactivematerial, such as activated carbon, coke breeze, peat moss, polymericion exchange resins, polymeric adsorbing resins; zero-valent iron,magnetite, apatite, organophilic clay, zeolite, diatomaceous earth ormixtures thereof and having a liquid-permeable outer geotextile sheetattached to the upper and lower major surfaces of the reactivematerial-containing geotextile.

BACKGROUND AND PRIOR ART

The prior art is replete with methods and articles used to confine orstore a wide variety of environmental contaminants ranging fromcompletely capping, in-situ, contaminated sediments that are leftin-place in underwater environments; terrestrial landfills whereindredged or otherwise collected contaminated sediments are placed withinan engineered disposal site surrounded with an impervious liner systemand capped with an impervious material; and the use of a reactive matand/or reactive backfill that surrounds the contaminated material.Examples of reactive mats are found in U.S. Pat. No. 6,284,681 B 1('681) and published application U.S. 2002/0151241 A1 ('241). Thereactive mats described in these two publications include one or morelayers of reactive material each surrounded by outer geotextiles thatallow contaminated liquid to pass through the reactive mat for sorptionor reaction of the contaminate with a reactive material containedbetween the outer geotextile layers, and in the case of the '241published application, the mat may be deployed vertically.

One of the major problems encountered with the use of reactive mats forcontrolling or confining contaminated materials, or in controlling orpreventing leaching of contaminants from sediments and preventing thecontaminants from entering ground water supplies, and particularly fromground water traversing upwardly through a lake or ocean soil interfaceinto the lake or ocean, is in the ability to provide a transportable,integral mat having a sufficient volume or thickness of reactivematerial so that the mat provides very long term protection without thenecessity of periodic replacement. The reactive mats described in the'681 patent and in the '241 publication provide alternating layers ofgeotextile/reactive material/geotextile/reactive material since asufficient thickness of reactive material cannot be provided in a singlereactive material core layer without that reactive material being lostduring transportation or installation. The mat disclosed in U.S. Pat.No. 7,128,498 does not have adjacent layers interconnected but reliesupon a rock covering layer to maintain the mat in position. The matdisclosed in the '498 patent has separate layers that are notstructurally interconnected and may easily separate due to the powerfulhydraulic force experienced with lake and river ground water supplies.Also, deployment of separate geotextiles and reactive materials througha water column is difficult.

This assignee's U.S. Pat. Nos. 5,237,945 ('945) and 5,389,166 ('166)describe the manufacture of a water barrier formed from a clay-fiber matthat may include a powdered or granular bentonite clay, a powdered orgranular liquid-interacting material, e.g., a contaminant-reactant, orproviding the contaminant-reactant as a separate layer in the waterbarrier product. The water barrier mat formed in accordance with the'945 and '166 patents is manufactured by laying down geosynthetic fibersand the water swellable clay, with or without the contaminant-reactantmaterial, simultaneously. In this manner, a geosynthetic compositematerial can be manufactured wherein the geosynthetic fibers aresurrounded by the water-swellable clay, with or without thecontaminant-reactant material, in initially forming a relatively thickgeotextile that essentially prevents water flow-through. Such a mat mustbe subsequently consolidated and the fibers must be substantiallydensified after the initial formation of the mixture of powdered orgranular material and fibers in an attempt to secure the fibers inposition surrounding the powdered or granular material. Densification ofthe fibers is achieved after the addition of powdered or granularmaterial since the fibers must be sufficiently spaced to allow forreceiving the powdered or granular material.

The following problems may be encountered with filled mats manufacturedby simultaneously mixing individual fibers together with powdered orgranular materials in accordance with this assignee's U.S. Pat. Nos.5,237,945 and 5,389,166:

(1) Because interior fibers within the geotextile are not secured toadjacent fibers, particularly in thick mats, there would be lateralmovement of powdered or granular material within the mat, particularlyat the center of the mat thickness;

(2) It has been found that any reactive materials that have a relativelyhigh hardness, e.g., zero valent iron, will prevent needlepunching as ameans to consolidate the mats described in the '945 and '166 patents,since the hard materials will cause needle breakage and frequentreplacement of worn needles;

(3) It has been found that needlepunching as a means to consolidate the'945 and'166 mats is limited to relatively thin mats, e.g., less than 1inch or 2.54 cm (25.4 mm), since fibers are too short to traverse thethickness of thicker mats, after receiving the reactive material, foreffective connection; and

(4) Because of the shifting of fibers and powdered or granular materialduring manufacture of the '945 and '166 mats, the powdered or granularmaterial will not be placed within the mat in a consistent quantity(weight per unit volume) and, therefore, will not provide consistentcontaminant reaction, contaminant sorption, or contaminantneutralization per unit area.

Another issue with the '945 and '166 mats is that when water swellablesodium bentonite clay is utilized, with or without the reactivematerial, when the sodium bentonite clay swells, the resulting swellpressure restricts the gaseous and aqueous flow through the mat. Gasesand ground water flow may flow around the barrier and escape withouttreating the contaminant(s).

SUMMARY

In brief, described herein are reactive geocomposite mats, and theirmethod of manufacture, for controlling contaminants in soil or waterthat allow the passage of essentially non-contaminated watertherethrough. The geocomposite mat includes a pre-formed woven ornon-woven geotextile, having a thickness of about 6 mm to about 200 mm,preferably about 10 mm to about 100 mm, and having a porosity sufficient(after being secured to a woven or non-woven outer geotextile or basesheet) to receive a powdered or granular contaminant-reactive material,contaminant-sorptive material, or a contaminant-neutralizing material(hereinafter collectively referred to as “contaminant-reactant material”or “contaminant-reactive material”) throughout its thickness, or in anyportion of the thickness, across its entire major surface(s). Thepowdered or granular contaminant-reactive material is disposed withinthe pores of the previously formed, high loft geotextile mat, afterneedlepunching the high loft geotextile to an outer geotextile sheetmaterial (woven or non-woven), to surround the fibers, e.g., by vacuumsuction or by vibrating the high loft mat while in contact with thecontaminant-reactive material to allow the powdered or granularcontaminant-reactive material to flow, by gravity and/or vibrationalforces, into the pores of the previously formed and needlepunchedgeotextile. Liquid-permeable outer geotextile sheets are adhered to theupper and lower major surfaces of the filled or partially filled highloft geotextile to substantially reduce the thickness and therebyincrease the density of the high loft geotextile fibers, andsubstantially increase the density of reactive material in gm/cm of highloft geotextile thickness (between upper and lower outer geotextilesheets), and to prevent the powdered or granular material from escapingfrom the geotextile during transportation and installation.Densification, by reduction in fiber thickness, after receiving thepowdered or granular material, aids in retaining the powdered orgranular material within the finished mat. To achieve the full advantageof the articles and methods disclosed herein, this further densificationis accomplished by heat sealing a cover sheet to heat softened, uppermat fibers during compression of the cover sheet onto the heat-softenedfibers. Optionally, the edges of the filled geotextile can be sealed,such as by providing the upper and lower cover sheets slightly largerthan the dimensions of the geotextile and gluing the extra cover sheetmaterial to the edges of the filled geotextile, or by heat sealing coversheet material to the edges. Other edge sealing options include sewing,needlepunching, and ultrasonic welding of the cover sheets together orby applying a separate, edge-covering material that can be glued, heatsealed or ultrasonically welded to the cover sheets. Edge sealingmaterials may be liquid-impermeable or liquid-permeable.

Suitable powdered or granular contaminant-reactive materials includeorganophilic clay, activated carbon, coke breeze, zero-valent iron,magnetite, apatite, zeolite, peat moss, polymeric ion exchange resins,polymeric adsorbents and mixtures thereof. If the contaminant-reactivematerial is lighter than water, such as activated coke breeze oractivated carbon, where the reactive mat is intended for sub-aqueousdisposition, the geotextile fibers will be a material that his heavierthan water, such as a polyester or a heavier material, such as sand, ismixed with the activated coke breeze and/or activated carbon to increasedensity. Any geosynthetic fibers may be used where the reactive materialis heavier than water, such as polyolefins, e.g., polypropylene,polyethylene and copolymers thereof; rayon; polyesters; nylon; acrylicpolymers and copolymers; polyamides; polyamide copolymers;polyurethanes, and the like.

The method of manufacture permits the manufacture of a geocompositearticle that includes a contaminant-reactant material that isstructurally secure, without lateral movement, and containscontaminant-reactant material uniformly disposed throughout thethickness, or throughout a desired upper and/or lower and/or centralportion of the thickness of the geocomposite. The geocomposite can bemanufactured to provide either a flexible or a rigid geocompositematerial, and permits the manufacture of various modified geocomposites;geocomposite articles that include a contaminant-reactant material, suchas a zeolite or an organophilic clay (with or without a water-absorbentmaterial) for treatment of contaminants in water, in an organic liquid,or in a mixture of water and an organic liquid; a minimum of leakage ofpowdered or granular materials held by the pre-formed mat; theapplication of layer(s) of liquid-permeable films or sheets of materialover both major surfaces of the article to confine the granular orpowdered material in place within the pre-formed geotextile; theapplication of solid or liquid adhesive materials or compositions to oneor both major surfaces and/or to any of the edges of the geocompositearticle for complete retention of essentially all powdered and/orgranular materials; the capability of inserting one or more rigidifyingmaterials into, or onto, the geocomposite article during manufacture,such as a sheet of perforated fiberglass; rope; cardboard; relativelyrigid, liquid-permeable corrugated materials, e.g., corrugatedcardboard, and the like at some point at or between the top and bottommajor surfaces of the geocomposite article to provide various degrees offlexibility or rigidity; the capability of manufacturing thegeocomposite articles by securing one outer geotextile sheet (preferablya lower geotextile sheet during manufacture) by needlepunching while thehigh loft material is not very dense (thereby minimizing needlebreakage) and prior to adding the reactive material, and then attachingthe remaining (preferably upper) geotextile sheet to the high loftinterior fibers, preferably by heat sealing, after the high loft fibershave been filled with the contaminant reactant material; and providingvarious sizes, shapes and weights of pre-formed, high loft geotextilesto achieve the benefits of each.

The contaminant-reactant material can be withheld from an upper or lowermajor surface of the high loft geotextile, if desired, to provide aspace or area for the addition of other powdered or granular materials,such as an organophilic clay, a zeolite, an activated carbon or othercontaminant-treating material or for heat bonding an upper surface ofthe high loft fibers to an upper geotextile sheet. For example, thecontaminant-reactant material can be omitted throughout a predeterminedthickness at the top major surface or the bottom major surface.Alternatively, a powdered or granular water-swellable clay material canbe applied in a relatively high concentration at or near the cut ends oredges of the geocomposite article adjacent to one or both major surfacesto permit the water-swellable clay to extrude through thewater-permeable cover layer to a planar edge surface immediately aboveand/or below one or both exterior major surfaces, thereby creating asealing layer of contaminant-reactant material capable of sealing atoverlaps and seams between adjacent or overlapping geocompositearticles.

Accordingly, one aspect of the geocomposite articles described herein isto provide a new and improved article of manufacture and method ofmaking the article by incorporating a powdered or granularcontaminant-reactant material into a high loft mat of geotextile fibersafter interconnecting the geotextile fibers to a cover sheet or layer.

A further aspect of the geocomposite articles described herein is toprovide a new and improved article of manufacture including a powderedor granular contaminant-reactant or contaminant-interacting material,wherein the material is selected from the group consisting of anorganophilic clay, a zeolite, a contaminant-absorbent, acontaminant-adsorbent, an ion-exchange material, a contaminant-reactant,a contaminant-neutralizing material, and mixtures thereof as separatelyapplied or intermixed material. The powdered or granular materials maybe applied as an admixture, or applied sequentially within a pre-formed,high loft textile mat after the high loft mat has been secured to ageotextile cover layer, and the high loft mat has an apparent openingsize of about 0.2 to about 6 mm, preferably about 0.84 mm to about 0.21mm, to receive the powdered or granular material in an amount of atleast about 10 lb/ft³ up to about 150 lb/ft³, preferably about 30 lb/ft³to about 100 lb/ft³, throughout the thickness, or throughout any upperor lower portion of the thickness of the pre-formed, high loft fibersresulting in an article that has a water permeability of at least 1×10⁻⁶cm/sec, preferably in the range of 10⁻⁴ to 10² cm/sec. Preferably, thepowdered and/or granular material will occupy about 50% to about 99.9%by volume of the pre-formed geotextile mat, more preferably about 80% toabout 99.9% of the pre-formed mat.

In terms of ft² of article surface area, some target loadings forvarious reactive materials (which can vary about 50% up or down) are asfollows: REACTANT LOADING Organoclay 0.82 lb/ft² 100% Carbon 0.53 lb/ft²100% Sand 0.92 lb/ft² 60% Carbon/40% Sand 0.67 lb/ft² 90% Carbon/10%Sand 0.56 lb/ft²

The above and other aspects and advantages of the geocomposite articlesand their method of manufacture will become apparent from the followingdetailed description of the preferred embodiments taken in conjunctionwith the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1, 3 and 4 are partially broken-away, schematic views of alternatemethods of manufacture and apparatus used to make the geocompositearticles described herein;

FIGS. 2 and 2A are enlarged, partially broken-away side views of apreferred embodiment of the reactive geocomposite article having a lowerwoven geotextile sheet attached to the high loft fibrous mat byneedlepunching and an upper, non-woven geotextile sheet adhered to thehigh loft fibrous mat by heat sealing;

FIG. 5 is a perspective view showing the geocomposite article describedherein oriented vertically, adjacent to a sea/soil interface, forsorbing contaminants, e.g., hydrocarbons from a petroleum spill, thatleach through soil and travel through the sea/soil interface, into thesea, to prevent the contaminants from traversing the sea/soil interface;

FIG. 6 is a partially broken-away side view of an edge of thegeocomposite article having excess material from upper and lower outergeotextile sheets adhered together, either adhesively, by heat-sealing,or by ultrasonic welding, to seal the edges of the article; and;

FIG. 7 is a schematic view showing the geocomposite article (reactivecore mat) disposed above a contaminated sediment, and weighted in placewith a sand cap layer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to FIG. 1, there is shown a schematic diagram for apreferred embodiment of manufacturing the geocomposite articles 10described herein, including many optional features any one or more ofwhich can be included in the manufacturing process to provide variouscharacteristics and properties to the geocomposite articles.

As shown in FIGS. 1 and 3, the preferred geocomposite article 10 ismanufactured to include a layer of woven or non-woven liquid-permeableouter geotextile sheet material layers on both major exterior surfaces;various optional reinforcing material can be included within theinterior and/or exterior of the article to provide structuralreinforcement or to provide various degrees of article rigidity;portions of the high loft geotextile, preferably made from thermoplasticfibers, e.g., a polypropylene, having inter-tangled, non-woven fibersthat are at least 5 cm. long, wherein the high loft geotextile remainsvery porous to allow for flow-through of contaminated water from belowafter being needlepunched to the lower outer geotextile sheet; and afterthe subsequent addition of the powdered or granular materials, such as acontaminant (organic) reactant absorbent or adsorbent; and, optionally awater-absorbent material, such as sodium bentonite clay and/or othersodium smectite clay, can be included (e.g., at seams) with thecontaminant-reactant material(s) being deposited onto the pre-formed,high loft geotextile. Any of these features can be used alone ortogether with any of the other features, as best shown in FIGS. 1 and 3,to provide very unique geocomposite articles having any number ofdifferent properties and the capability of containing the spread ofcontaminants.

As shown in FIGS. 1 and 3, there are illustrated methods and apparatus,including a number of optional features each of which can be used aloneor in combination with any of the other features, for manufacturing aproduct having single or plurality of different granular or powderedcontaminant-reactant materials, and with or without various reinforcingmaterials and/or coating materials added to one or both exteriorsurfaces of the article being manufactured to provide variouscharacteristics or properties to the finished geocomposite article 10,as will be described in more detail hereinafter.

In accordance with a preferred embodiment, as shown in FIG. 1, high loftfibers 14 are needlepunched to a bottom cover layer at an off-siteneedlepunching facility and obtained from the needlepunching facility asa roll of material 12 that is subsequently loaded onto mandrel 9. At theneedlepunching facility, high loft fibers 14 are needlepunched to awoven or non-woven, lower water pervious cover sheet 16. To achieve thefull advantage of the articles and methods of manufacture describedherein, the high loft fibers 14 needlepunched to the lower cover sheet16 should be in a concentration or mass of about 300 to about 450 gramsof loose fiber per square meter of cover sheet 16 surface area when thefibers 14 are needlepunched to the cover sheet 16. If the mass of thefibers 14 needlepunched to the lower cover sheet 16 is less than about300 g/m², the fibers 14 may not provide sufficient void spaces to hold asufficient quantity of powdered or granular reactive material. If themass of fibers 14 is greater than about 450 g/m², needlepunching may notsecurely attach the high loft fibers 14 to the cover sheet 16 and thefibers 14 may peel away from the cover sheet 16.

In the preferred embodiment of the needlepunching operation (not shownin FIG. 1) required to provide the roll of composite (high loft andcover sheet) material 12 with both sufficient open pore volume orapparent opening size and sufficient strength, a needle density shouldbe provided that is sufficient to provide at least 0.5 lb/in, preferablyat least 1.0 lb/in, in peel value when tested in accordance with ASTMtest Designation: D-4632 (Re-approved 2003), the standard Test Method ofGrab Breaking Load and Elongation of Geotextiles, modified for theneedlepunched material 12, as follows:

The test for the composite material 12 utilizes the same 4″×8″ samplesize as in ASTM D-4632. Instead of test mounting a geotextile in twogrips, the needlepunched high-loft composite 12 is tested by separatingthe high-loft fibers 14 from the woven geotextile 16 at the top andbottom. The high-loft fibers 14 are secured in one grip and thegeotextile (preferably woven, 16) in the other grip. The peak value of 5specimens are averaged. The target value is preferably 1 lb/in peel onthe interface between the woven cover sheet 16 and the high loftnon-woven fibers 14.

As shown in FIG. 1, the composite material is unwound such that theneedlepunched, high loft fibers 14 contact textured roller 18 to extendthe fibers 14 outwardly from the lower cover sheet 16 that the fibers 14are needlepunched into. The outward extension of fibers 14, or fluffingof the fibers 14, returns the fibers 14 to their high loft and porouscondition after needlepunching and before being compacted into the rollof composite material 12.

After the needlepunched fibers 14 are fluffed by textured roller 18, thecomposite material comprising the lower cover sheet 16 and fluffedneedlepunched fibers 14 is conveyed under reactive material hopper 20and feed conveyor 21 and over vibrator 22, where the reactive materialis deposited from feed conveyor 21 and vibrated into the needlepunched,porous fibers 14.

In the preferred embodiment, a water-pervious cover sheet 24 then isdisposed over the composite material comprising the lower,water-pervious cover sheet 16, and needlepunched fibers 14 containingthe reactive material. To achieve the full advantage of the articles andmethods of manufacturing described herein, the cover sheet 24 isheat-melt adhered to the upper surface of the upwardly extending fibers14 to enclose the fiber-contained reactive material between thewater-pervious lower cover sheet 16 and water-pervious upper cover sheet24. As shown in FIG. 1, a heat source, e.g., a heat gun 30, ispositioned to supply heat at a pair of nip rollers 26,28 to heat a lowersurface of the cover sheet 24 at the same time as heating the upwardlyextending, randomly oriented fibers 14. Enough heat is supplied at themeeting point of cover sheet 24, preferably a polyolefin, such aspolyethylene or polypropylene, and fibers 14 to heat-soften or melteither the undersurface of cover layer 24 or upwardly extending fibers14, or both, so that when the softened geotextile sheet 14 and/orgeotextile fibers 14 are compressed between nip rollers 26 and 28 andsubsequently cooled, the cover sheet 24 is heat-sealed to the fibers 14.

In accordance with a preferred embodiment of the articles and methodsdescribed herein, the heating device, e.g., heat gun(s) 30, ispositioned across the entire width of the geocomposite article 10 beingmanufactured. After heat sealing, the article 10 travels through guiderolls 32,34 on route to an accumulator 36 containing alternate, upwardlyreciprocating rollers 38,40 and 42 that move upwardly to accumulateproduct 10 when a completed roll of product is removed from productstation 44 or 46. In this manner, the manufacturing process remainscontinuously producing product during removal of a roll and duringpositioned of product onto a different mandrel at product station 44 or46. Guide rollers 48 and 50 guide the product to product station 44 or46.

The liquid-permeable sheet material layers 14 and 24, are used toprevent loss of the powdered or granular material during transportationand installation. To achieve the full advantage of the articles andmethods described herein, the high loft fibers 14 are needlepunched togeotextile sheet 16 (preferably woven) before being loaded onto mandrel9 resulting in a needlepunched mat having a density of about 0.90 toabout 2.0 lb/ft³ for the high loft geotextile fibers 14, preferablyabout 0.94 to about 1.6 lb/ft³ at a thickness of about 0.5 to 1.1inches. The preferred method of manufacture is to first adhere the lowerliquid permeable geotextile sheet material layer 16 to the high loftfibers 14 by needlepunching, followed by filling or partially fillingthe high loft geotextile fibers 14 with the powdered or granularmaterial, followed by heat sealing the upper, liquid-permeable outergeotextile sheet material 24 to heat-softened, upwardly extending fibers14A (FIG. 3) of the high loft geotextile fibers 14 containing thepowdered or granular material. In a preferred embodiment, heat guns 30heat the upwardly extending fibers 14A of the high loft geotextile 14and the undersurface of the upper geotextile cover sheet 24 to theirsoftening (melting) point and the cover sheet is compressed against theheat softened, upwardly extending fibers 14A to heat seal them to thecover sheet 24, without forming a continuous, water-impermeableimpermeable film on the under surface of the upper cover layer 24. Inone embodiment, the powdered or granular material penetrates the highloft fiber 14 by vibrating the composite article with vibrator 22.Alternatively, vacuum 140 (FIG. 3) can be applied under the geotextilein place of vibrator 22.

As shown in the schematic illustration of FIG. 3, including aneedlepunching station 36 and vacuum apparatus 140, additionalcontaminant-reactive material in granular or powdered form can beapplied to the filled geotextile fibers 14 from an additional feedinghopper 24 to provide one or more surface concentrations ofcontaminant-reactive material or to apply a different powdered orgranular contaminant-reactive, prior to applying the water-permeablecover layer 24. The upper major surface 14A of the high loft geotextilefibers 14 are then heat sealed to the upper, preferably non-woven, coverlayer 24, from roll 29, as described. In accordance with an importantfeature of the articles and methods described herein, the upper coverlayer 24 is heat-sealed to the upwardly extending fibers 14A of thegeotextile fibers 14, creating a discontinuous bond so that the articles10 remain water-permeable.

In a separate operation, needlepunching, in the preferred embodiment, isprovided to secure the high loft fibers 14 to the lower, outergeotextile sheet 16 (preferably woven) to interlock the high loftgeotextile fibers 14 to the lower cover sheet 16 to provide sufficientstrength, and sufficient reactive material, to the final article 10. Thefinished article 10 can be collected in a roll form 40, taken up on asuitable mandrel 42, or can be festooned onto pallets (not shown) or thelike.

As shown in the schematic of FIG. 4, there is shown one method ofloading high loft geotextile fibers 114 with powdered or granularcontaminant-reactant material in a dry state. The dry material feedingapparatus, generally designated by reference numeral 100 is useful fordepositing one or more powdered or granular contaminant-reactantmaterials, such as an organophillic clay, from a receiving hopper 102.An auger 104 is disposed at a lower end of the receiving hopper 102, andin fluid communication therewith, to force the contaminant-reactantmaterial through conduit 106 to an inlet 108 of elevator 110. Thecontaminant-reactant is discharged from the elevator 110 at elevatoroutlet opening 112, through conduit 114 into a receiving hopper 116. Apair of augers 118 and 120 in fluid communication with a lower portionof hopper 116 force the contaminant-reactant into one, two or threefeeding mechanisms, generally designated by reference numerals 122, 124and 126, for feeding the contaminant-reactant material in a controlledmanner to one, two or three continuous feed conveyor belts 128, 130 and132 successively aligned above an elongated product conveyor belt 134.The contaminant-reactant generally is applied over the high loft,geotextile mat 114 to substantially fill the void spaces between fibersin the high loft, geotextile mat 114 in an amount of about 1/4 to 30pounds of powdered or granular material per square foot of finishedarticle major surface area, preferably about 1/4 to about 5 pounds ofpowdered or granular material per square foot of article major surfacearea.

In accordance with one embodiment shown in FIG. 4, the upper surface114A of the high loft geotextile fibers 114, after filling, is thenheated by heat gun 21 (extending across the entire upper surface ofgeotextile fibers 14) to the fiber softening point as the upper (cover)sheet material (layer 150) is pressed onto the softened, high loftfibers by compression roller 152 to discontinuously adhere the outergeotextile sheet material layer 150 to an upper surface of the high loftgeotextile 114 after the geotextile 114 has been filled from one or moreof the feeding mechanisms 122, 124 and/or 126, deposited onto thegeotextile 115 from one, two or all three of the feed conveyor belts128, 130 and 132. Any one, two or all three of the feed conveyor belts128, 130 and 132 can be used to incorporate the same or differentpowdered or granular contaminant-reactant materials throughout a portionof, or the entire thickness of the geotextile 114. Vibration apparatus140 is connected to the product conveyor belt directly below the feedconveyor belts 128, 130, and 132 to vibrate the powdered or granularcontaminant-reactant materials into the geotextile 114.

The individual powdered or granular materials are deposited across theentire width of the geotextile fibers 114, as the particles drop fromthe feeders 122, 124 and/or 126. In this manner, the entire thickness orany portion of the thickness of the high loft fibrous mat 114 is filledwith the contaminant-reactant material. Dust collection suction devices144, 146 and 148 may be disposed near each continuouscontaminant-reactant feed conveyor belt 128, 130 and 132 to clear theair of fine particles emanating from feeding mechanisms 122, 124 and 126and return the particles back to a dust collector 167 for disposaland/or back to the receiving hopper 102, via conduit 149. The upper(cover) water-permeable sheet material 150, from roll 151, is disposedon a downstream side of the powdered or granular material feedingmechanisms 122, 124, and 126 and above the product conveyor belt 134.The second flexible, water-permeable sheet material 150 preferably is anon-woven and is fed by power driven roller 152, power rollers 154 and156 and wind up rollers 158 and 160 to dispose flexible, water-permeablesheet material 150 on top of the contaminant-reactant-filled article todispose the filled geotextile material 114 between lower,water-permeable flexible sheet material 136 and upper, water-permeableflexible sheet material 150.

The powdered or granular contaminant-reactant material utilized to fillthe void spaces between the fibers of the high loft, geotextile 114 hasa particle size in the range of about 1 to about 400 mesh, preferablyabout 10 to about 200 mesh.

Some of the most prevalent contaminants found in waste waters containedin ponds, lagoons, areas of subterranean structure and otherwater-releasing or organic (hydrocarbon) spill areas, particularly wherethese areas include industrial waste waters, are heavy metal ions andwater-insoluble or partially water-insoluble organic materials. It iswell known in the prior art that natural and synthetic zeolites and ionexchange resins are capable of removing a substantial portion of theheavy metal ions from a waste water solution and that organophilic claysare capable of removing water-insoluble organic materials from solution.However, the prior art suggests that removal of these materials fromwaste water streams should be done on-stream, treating the entirety ofthe waste water stream in order to remove these materials, requiringfrequent replacement of treating materials because of the heavy volumesof waste water stream that passes through the zeolites or passes throughthe organophilic clays in order to clarify these waste water streams. Byincluding an organophilic clay, or applying a mixture of water-swellableclay (not required) with a zeolite or organophilic clay, to fill thevoids between fibers of the high loft geotextile 14 (FIG. 1) or 114(FIG. 4), the zeolite and/or organophilic clay will form awater-treatment material wherein the zeolite and/or organophilic claywill remove the contaminants, e.g., hydrocarbon contaminants, and allowthe clean water to pass through the article 10 as shown in FIG. 7.

As shown in FIG. 5, the articles 10 described herein are particularlyeffective for vertical disposition adjacent to a sea/soil interface 200for protecting a lake or ocean 202 against hydrocarbon contaminants thatotherwise leach through soil 204 and penetrate the sea/soil interface200.

In accordance with another important embodiment of the articlesdescribed herein, the contaminant-reactant material, comprising anycontaminant-adsorbent, -absorbent, -reactant, or -neutralizing materialcan be supplied as a separate layer adjacent to another powdered orgranular contaminant-reactant material so that the amount of materialtreated for the removal of a given contaminant is only that materialwhich penetrates the adjacent layer of powdered or granular material.

In accordance with another important feature of the articles and methodsdescribed herein, the contaminant-reactant materials mixed or suppliedas separate layers can be any material capable of adsorbing, absorbing,neutralizing, or reacting with the contaminant for insolubilizationand/or separation of the contaminant from the liquid stream flowingthrough the reactive material. Examples of materials capable of removingor neutralizing contaminants include absorbent fibers, such asmicrocrystalline cellulose; attapulgite clay; apatite; zinc rincinoleateabsorbed on an absorbent fiber or other absorbent material; amorphoussilica powder; synthetic calcium silicate; polyolefin pulp; sodiumalumino-silicate (type A sodium zeolite); maltodextran; sodium silicaaluminates (note that all the above are absorbents). Other materials,such as adsorbents include microcrystalline cellulose; silica hydrogelbased compositions; attapulgites; synthetic sodium magnesium silicates;synthetic calcium silicates; silicon dioxide; acid activated clays; typeA sodium zeolites; and the like provided as a separate layer or mixedwith the absorbents and/or adsorbents. Other materials can be includedsuch as an algicide, antimicrobial material, bactericide, disinfectant,and/or fungicides such as phenol; zinc undecylenate N.F.; acetyltyridinium chloride N.F.X.III and the like.

Most preferred as the adsorbent, absorbent and/or reactant and/orneutralizing material are coke breeze, activated carbon, zero-valentiron, magnetite, natural or synthetic zeolites, apatite, and/or anorganophilic clay, which is basically a montmorillonite clay that hasbeen reacted with a quaternary organic material to make it hydrophobicand absorbent to organic contaminants.

The high loft geotextile fibers 14 or 114 preferably is a high loftnon-woven. Suitable fibers of construction of the geotextile mat 14 or114 include fibers made from rayon, polypropylene, polyesters, nylon,acrylic polymers and copolymers, ceramic fiber, fiberglass,propylene-ethylene copolymers, polypropylene-polyamide copolymers, asingle monofilament, polyethylene, polyurethane, cotton, jute and anyother non-biodegradable, or very slowly biodegradable, fibers preferablyhaving both bacteriological and chemical resistance. In someinstallations, the thickness of the article is not important and sucharticles can be formed with any desired thickness, e.g., 3 mils to about4 inches containing about 0.2 to about 30 pounds per square foot ofcontaminant-reactant material.

The above-described products can be modified in a number of ways to suitvarious purposes and this adaptability of the products is one of theprimary benefits when compared with water barriers of the prior art. Forexample, the products described herein can be loaded with a heavymaterial such as sand, or a heavy mineral such as Barite, iron oxide orthe like, relatively uniformly, together with a powdered or granularcontaminant-reactant so that the overall product has a specific gravitygreater than 1.0 thereby enabling the material to submerge easily inwater. Accordingly, the product can be applied to the sediment surfaceat the bottom of a lake, bay, river, waterway, filled lagoon, wastecontainment area, and the like, without first draining the lagoon orwaste containment area. The product containing a heavy mineral can berolled out over the water or waste containment upper level and allowedto sink to cover the sediment surface at the bottom of the water orliquid waste material, thereby saving substantial time, effort andexpense in sealing an area, and the like, without first draining thearea.

In another embodiment, the products described herein can haveincorporated therein a very light material such as expanded vermiculiteor expanded perlite, so that the product has substantial buoyancy inwater, liquid waste materials, and the like, to form a cover over aliquid waste containment area, such as a toxic waste lagoon, to preventexternal compounds, dust, and dirt from entering the waste containmentarea. One portion of this cover material can be adapted for removal orrolling back so that additional toxic waste and the like may be added tothe covered containment area while maintaining a water-impervious coverto prevent further filling of the waste containment area with rainwater.

Drainage structures and other articles used in the water drainage artscan be virtually incorporated into the interior of this product duringmanufacture, e.g., under the upper and/or lower outer geotextile sheets.Herbicides, bactericidal materials, tracer chemicals, various colorantsthat indicate contact with a particular chemical or class of chemicals,and the like, also can be incorporated into the articles describedherein.

The product is particularly effective in shored wall conditions forapplication against steel sheet piling; soldier beam and lagging;soldier beam and earth installations; concrete caissons; earthenstabilized wall structures and soil/sea interface wall structures. Inaddition to the usual geotextile-type fibers, cellulosic fibers can beused as well as hay, straw, coconut fibers and fibers refined from woodchips and the like, particularly for use as an agricultural root zoneliner to provide liquid feed for the promotion of plant growth. Theproducts described herein are also useful as gas barriers, particularlyRadon gas barriers, to protect structures and containers above or belowground. Many other uses for the products of the present invention shouldbe apparent to those skilled in the art.

The uses for the powdered or granular material-filled orpartially-filled products described herein are virtually infinite sincethe product can be made completely flexible, relatively rigid or rigidand can be applied against very contoured and slopping surfaces, roughor smooth, as well as vertical surfaces, such as foundation walls, dams,along the sides of canals and below grades such as in tank farms, andfor irrigation and water conservation techniques. The products areparticularly well suited for providing contaminant-removal in shoredwall conditions to protect surface areas that are vertical, sloped orhorizontal.

1. A reactive geocomposite article for treating contaminants in soil orwater comprising a pre-formed geotextile mat formed from non-wovengeotextile fibers, having a thickness of about 6 mm to about 200 mm andhaving upper and lower major surfaces, wherein the non-woven fibers havevoid spaces that provide sufficient porosity to receive a powdered orgranular reactive material and the geotextile article remainswater-pervious; a powdered or granular reactive material disposed withinat least a portion of the void spaces of the geotextile mat andsurrounding some of the geotextile fibers of said geotextile mat;liquid-permeable outer geotextile sheets adhered to the upper and lowermajor surfaces by needlepunching non-woven fibers to one of the outergeotextile sheets before adding the powdered or granular materialthereto, and then, after adding the powdered or granular material to thegeotextile mat, adhering the remaining outer geotextile sheet to theneedlepunched geotextile mat to confine the reactive materials withinthe geotextile article, between the outer geotextile sheets.
 2. Thereactive geocomposite article of claim 1, wherein the powdered orgranular reactive material is selected from the group consisting ofactivated carbon, coke breeze, zero-valent iron, magnetite, apatite,organophilic clay, zeolite, polymeric ion exchange resins, polymericadsorbing resins and mixtures thereof.
 3. The reactive geocompositearticle of claim 1, wherein the geotextile fibers are selected from thegroup consisting of polyolefin, polyester, polyamide, and copolymers ofany two or more of the foregoing.
 4. The reactive geocomposite articleof claim 2, wherein the reactive material is an adsorbent materialselected from the group consisting of activated carbon, coke breeze,organophilic clay, and any combination thereof.
 5. The reactivegeocomposite article of claim 1, wherein the pre-formed geotextile,prior to receiving the powdered or granular reactive material, has anapparent opening size in the range of about 0.2 mm to about 6 mm.
 6. Thereactive geocomposite article of claim 5, wherein the powdered orgranular reactive material has a particle size such that at least 90% ofthe particles have a size in the range of about 6 mesh to about 325mesh.
 7. The reactive geocomposite article of claim 5, wherein thepowdered or granular reactive material comprises about 50% to about99.9% by volume of the geotextile mat.
 8. The reactive geocompositearticle of claim 1, wherein the geocomposite article has 30 lb/ft³ to100 lb/ft³ of powdered or granular reactive material contained therein.9. The reactive geocomposite article of claim 3, wherein the geotextilefibers are selected from the group consisting of polyethylene fibers,polypropylene fibers, polyester fibers and polyamide fibers.
 10. Thereactive geocomposite article of claim 1, wherein the pre-formedgeotextile mat is woven with non-woven fibers.
 11. The reactivegeocomposite article of claim 10, wherein the needlepunchedliquid-permeable outer geotextile sheet is woven and the other outergeotextile sheet is a non-woven sheet.
 12. The reactive geocompositearticle of claim 11, wherein the other outer geotextile sheet is adheredto the needlepunched geotextile mat by heat sealing, sonic welding, oradhesively.
 13. A method of manufacturing a geocomposite article capableof sorbing, reacting with, or neutralizing a liquid-containedcontaminant comprising: providing a pre-formed geotextile mat having anapparent opening size greater than 6 mm and having opposed majorsurfaces; needlepunching the pre-formed geotextile mat to an outergeotextile sheet to a degree sufficient to densify the pre-formedgeotextile mat sufficiently to provide the needlepunched mat with anapparent opening size in the range of about 0.2 mm to about 6 mm;contacting an uncovered major surface of the geotextile mat with apowdered or granular material capable of sorbing, reacting with, orneutralizing the liquid-contained contaminant, and causing the powderedor granular material to flow into the pre-formed, needlepunchedgeotextile mat to fill at least a portion of the pre-formedneedlepunched geotextile mat within openings of the mat; and adhering aliquid-permeable outer geotextile sheet to the uncovered major surfaceof the pre-formed, needlepunched geotextile mat after the mat hasreceived the powdered or granular material.
 14. The method of claim 13,further including the step of covering edges of the pre-formedgeotextile mat with a sheet material layer.
 15. The method of claim 14,wherein the edges of the geotextile mat are covered with excess materialfrom one or both of the outer geotextile sheets.
 16. The method of claim15 wherein the excess material of the outer geotextile sheets aresecured together to cover the edges of the geotextile mat by adhesivelysecuring the outer geotextile sheets together over the edges of thegeotextile mat, or heat-sealing the outer geotextile sheets togethersurrounding the edges of the geotextile mat.
 17. The method of claim 13,wherein the powdered or granular material is caused to flow into thegeotextile mat by vibrating the geotextile while in contact with thepowdered or granular material.
 18. The method of claim 13, wherein thepowdered or granular material is caused to flow into the geotextile byapplying a vacuum to an undersurface of the geotextile to draw thepowdered or granular material into the mat from an upper surface. 19.The method of claim 13 further including the step of providing at leastone of the outer geotextile sheets having a dimension larger than themajor surface of the geotextile mat to provide excess outer geotextilesheet material so that the excess outer geotextile sheet materialextends over an edge surface of the geotextile mat, and securing theexcess outer geotextile material to the geotextile mat to cover the edgesurface, thereby reducing or eliminating escape of powdered or granularmaterial through the covered edge surface of the geotextile article. 20.The method of claim 13, wherein the outer geotextile sheet adhered tothe geotextile mat, after adding the powdered or granular material, isheat sealed to the geotextile mat.
 21. The method of claim 20, whereinthe outer geotextile sheet is heat sealed to the uncovered major surfaceof the geotextile mat by heating upwardly extending fibers from thegeotextile mat to their softening temperature and then pressing thecover sheet against the softened fibers.
 22. The method of claim 19,including the step of covering all edge surfaces with excess outergeotextile sheet material, and securing the excess outer geotextilesheet material to the geotextile mat thereby reducing or eliminatingescape of powdered or granular material through all edge surfaces of thegeotextile article.
 23. The method of claim 19, wherein the outergeotextile sheet is secured over the edge surface by an expedientselected from the group consisting of adhesively securing,needlepunching and ultrasonic welding.
 24. The method of claim 22,wherein at least one of the outer geotextile sheets is secured over alledge surfaces by an expedient selected from the group consisting ofadhesively securing, needlepunching and ultrasonic welding.
 25. Themethod of claim 13, wherein the uncovered major surface of thepre-formed geotextile mat is adhered to the outer geotextile sheet by awater-insoluble adhesive, or by heat-sealing, or by sonic welding afterthe needlepunched geotextile mat has received the powdered or granularmaterial.